Manufacture of sand-paper



(No Model.) 2 Sheets-Sheet 1-.

G. BAEDER.

MANUFACTURE OF'SAND PAPER, No. 265,940. Patented 001;.1'7, 1882.

M97 EJQ k wmmm n, a

(No Model.) 2 Sheets-Sheet 2..

G. BAEDER.

MANUFACTURE OF SAND PAPER.

Patented Oct. 17, 1882 Inv e 7210) saw X724.

PATENT @FFICE.

CHARLES BAEDER, OF JENKINTOWN, PENNSYLVANIA.

MANUFACTURE OF SANIJ-PAPER.

SPECIFICATION forming part of Letters Patent No. 265,940, dated October17, 1882,

Application filed June 17, 1882. (No model.)

To all whom it may concern Be it known that I, CHARLES BAEDER, ofJenkintown, in the county of Montgomery and State of Pennsylvania, haveinvented certain new and useful Improvements in the MannfactureofSand-Paper, of which improvements the following is aspecitication,reference being had to the accompanyingdrawings, which form a partthereof.

Myiuvention is applicable alike to the manufacture of emery-paper orglass-paper, and to the use of cloth instead of paper in suchmanufactures. It will therefore be understood that although the termsand-paper is used in the following specification, the description isequal- 1y applicable to these other analogous manufactures.

The ordinary method ofmaking sandpaper is to pass the paper over aroller revolvingin mta trough of melted glue, so that the roller preadsthe glue on the under side of the paper. The paper is then passed overother rollers, so that the glue-coated surface is broughtuppermost, andthe sand is sprinkled over it while the paper is being drawn along thesurface of a table or apron. From this table or apron the glued andsanded paper is conveyed to racks or frames, upon which it is left todry. When thus finished the surface of the paper is often found to beuneven. The sand is not uniformly applied, and is thicker and adheresmore closely at some places than at others, and both glue and sand aregenerally found upon the under surface or back of the paper along theedges. The removal of this superfluous glue and sand is very desirable;but it is so difficult that frequently it is found necessary to trim offthe overfiowed edges of the sheet, thus wasting a large portion of theproduct. Moreover, the sand is readily detached when the paper is used,and the surface is thus rapidly worn off.

The object of my invention is to obviate all these difficulties, and toproduce a sand-paper having a durable, firm, and uniform abrasivesurface, while its opposite side shall be free from glue and sand, and Iaccomplish this result as follows: After the paper has passed from thegluing-roller, from which it receives the coating of glue upon one side,I subject the opposite side to the action of scrapers, which remove anyglue that has found access to that side, and after the sanding processhas been effected and while the glue is still soft I subject the coatedsurface to positive pressure, so as to embed the sand in the glue, andat the same time repeat the scraping of the uncoated surface. I thenfinallypass the paper through sizing-rollers, by which the sand is stillfurther secured upon the surface, and from these rollers I lead thefinished sized paper to the drying-racks. By this pressure the sand isforced deeply and tightly into the glue upon the coated side of thesheet and uniformly distributed thereon, while the continuousapplication of the scrapers to its under surface during the process ofmanufacture and before the gluehas become hard insures the removal ofanyglue and sand that have found their way onto the uncoated side of thepaper, and the sizing operation prevents the sanded surface from beingso rapidly worn away in use.

In the accompanying drawings, Figure 1 is a vertical longitudinalsection through the center of a machine embodying my improvements andadapted to the conduct of my improved process. Fig. 2 is a sideelevation of the same. Fig. 3 is a plan or top view of the machine withthe upper portion of the frame-work removed, and Fig. 4 is a verticaltransverse section on the line at w of Fig. 1.

A stout frame-work consisting of the pieces A A, B B, and O G affordsbearings for the various revolving shafts, and supports the gluing andsanding and sizing devices.

D is the glue-trough, which is kept supplied with melted glue to a depthsufficient to nearly immerse the roller (1. A second roller d, isarranged above the roller d and nearly in contact therewith. The severalcarrying-rollers R R R R R R It It are placed in the various positionsindicated to support and convey the sheet of paper through the machine,and are all positively rotated by means of belting L L L L, 850., drivenfrom the main shaft or pulley Gr.

Adjacent to the glue-trough D is the sanding device, which consists of ascreen or sieve,

the framework E. The pendent strip of steel j, fixed at its upper endupon the frame E, presses against one side of the sieve F, while F,sliding laterally on ways u, mounted upon at the opposite side aremounted springs Z Z. A shaft, f, provided with a cam, g, bearing againstthe stripf, is rotated by means of bevelgears e 0, and serves, with thesprings Z Z, to give the sieve F a rapid reciprocating or oscillatingmotion from side to side of the machine.

A sand-box, Q, is arranged conveniently at the side of the sieve, fromwhence the workman can replenish the latter as the sand is siftedthrough it, while a trough or chute, t, is placed beneath to receive theloose sand which falls off from the sheet.

Beneath the sieve F, and also adjacent thereto, is a series of steelblades or scrapers, s s s s s 3, parallel to one another and fixedtightly upon the frame z, which fits snugly between the sides of themain frame B B. These blades extend across the entire width of thepaper, strip, or sheet, and are moderately sharpened upon their upperedges. They may be separately adjustable vertically in the frame a, ormay be fixed therein, in which latter case I construct the frame a sothat it can be adjusted vertically. The number of the scrapers 8 may bevaried for work of different characters; but ordinarily I have foundthat a series of six -or seven blades arranged as shown gives goodresults. 4

Pressure-rollers M" of metal, turned true, are arranged above the spacebetween the pairs of scrapers s, theirjournals being mounted in slot tedstandards, beyond which they project, as indicated in Figs. 2 and 3, sothat they can be weighted in case additional pressure is required. Theslots of the bearings are so arranged as to permit the descent of therollers to a depth of about one-half their diameter between thescrapers. The number of the rollers r 1 may be varied with that of thescrapers, and I have obtained good results by placing a supplementalseries of scrapers and rollers at a considerable distance (in the pathof the paper) from the first series. This supplemental series isindicated in Fig. 1 at 1' r and s s.

T is'a sand-collector or trough to receive the surplus sand which fallsoff from the traveling sheet after it passes the rollers r 'r, and isprovided with a screw, S, by which the sand is discharged at one endinto a suitable receptacle. O is a revolving beater, which aids indetaching the loose sand from the surface.

The heavy pressure-rollers I J, the latter of which is journaled uponthe swinging arms 1', are positively rotated by belting L L. Thesurfaces of the rollers I J are carefully turned true, so that thecontact and pressure between them is exact and uniform, and the lowerportions of their peripheries are immersed in hotwater vessels H H",respectively, so as to soften any glue that may stick to them and permitits removal by the hard-rubber scrapers c '0. In addition to thescrapers o a, I contemplate using brushes which revolve in contact withthe rollers I J to clean them.

The operation of the apparatus in the conduct of my improved process isas follows:

The paper is fed from a roll or continuous sheet, P, and moves in thedirection of the arrows. Starting from roller 1) it passes between thegluing-rollers d d, from theformer of which its under surface receives acoating of the melted glue. As the sheet passes over the roller d theglued surface is brought uppermost and drawn beneath the sieve F. Thevibration of the sieve F showers the sand down in excess upon the gluedsurface, to which a portion of it adheres. At this stage the action ofthe scrapers s 8 begins, the sheet being pressed against their edges atfirst by its own weight and subsequently, as the sheet moves forward, bythe positive pressure of the rollers r r, which is limited only by thetensile strength of the sheet. The rollers r r not only insure the moreefficient action of the scrapers in removing glue and sand from theunder surface of the sheet, but distribute the excess of sand evenlyover the upper surface, and press the bottom layer of sand into theglue, thus insuring a uniform and permanent sanded surface. As the sheetpasses on it is again turned over, as shown, upon the roller above thetrough T and slightly shaken by the revolving heater 0,

by which means the surplus sand is thrown oft into the box T, whence itis removed by the screw S and restored to the sand-box Q. After thisseparation of the surplus sand the sheet, now provided with its properquantity, is drawn up between the heavy pressure-rollers I J, whichfirmly embed the sand into the still soi't glue and smooth out anyaccidental inequalities that may have passed the first rollers.

Beyond the pressure-rollers I J, I arrange, in a suitable frame, asecond trough similar to D, provided with a pair of rollers similar to dand d in construction, arrangement, and operation, and being aduplication of that apparatus l have deemed it unnecessary to show it inthe drawings. This second trough is supplied with a proper sizingpreparation, and the glued and sanded paper passes from thepressure-rollers I J between these sizing-rollers, from the lower one ofwhich the sanded surface receives a thin coat of sizing, and then thepaper passes on and moves upward over the supporting-roller and betweenthe light rollers r r and the scrapers s s, which scrapers re-' move anysizing that may have accumulated on the under edge of the paper, whilethelight rollers smooth down the sized surface of the paper, and thusthe sand is further secured by an outer surface, which gives it greatadditional cohesion and prevents it being rapidly worn off in use. Fromthese light rollers and scrapers the finished sheet passes over theremaining carrying-rollers to a point, as P, from which it is led off tothe drying-racks. By this means I accomplish at one passage through theapparatus what would otherwise require two separate operations,involving a loss of half of the time.

It is obvious that various modifications of the arrangement above namedmay be em- IIO IIS

ployed without departing from the principle of my invention, and thatvariations of the number, weight, and position of the pressurerollersand of the number of the scrapers may be found advantageous fordifferent grades of product. Thus, for instance, where very fine emerycloth or paper is to be manufactured, sufficient pressure may beobtained from the light rollers such as 1'1, and the use of the heavypressure-rollers I J may be dispensed with. I do not deem it necessaryto describe all these variations in the process or apparatus, which willbe obvious to the experienced workman in conducting the manufacture, andtherefore while I have described an arrangement and mode of treatmentwhich give good results for the manufacture of the ordinary grades ofsand-paper, 1 do not wish to be understood as disclaiming other changesin detail by. which myimproved process can be car ried out.

Having thus described the nature and object of my improvements, whatIclaim as new, and desire to secure by Letters Patent, is-

1. As an improvement in the process of manufacturing sand-paper andsimilar products, subjecting the glued and sanded surface, while theglue is still soft, to positive and uniform pressure, substantially asset forth.

2. As an improvement in the manufacture of sand-paper and similarproducts, subjecting the glued and sanded surface continuously to asecondary s zing operation, substantially as and for the purposedescribed.

3. In an apparatus for the manufacture of 5 sand-paper and similarproducts, the combination of rollers and scrapers, substantially asdescribed, whereby the sheet is simultaneously rolled upon its uppersurface and scraped upon its under surface while the glue is still soft,for the purpose set forth.

4. In an apparatus for manufacturing sand" paper and similar products,scrapers applied and operating upon the under side of the pa-'

